Final Rules Set On Car Mileage

By

Ryan Tracy

Updated Aug. 28, 2012 9:20 p.m. ET

The Obama administration released final fuel-economy standards that are set to nearly double the average mileage of cars and light trucks to 54.5 miles per gallon by 2025, risking some political backlash in an effort to curb U.S. oil consumption and greenhouse-gas emissions.

The standards, almost identical to those proposed by the administration in November, would require steady increases in fuel efficiency for new cars built between...